Clonidine and apraclonidine

Apraclonidine is contraindicated in patients sensitive to clonidine and those taking monoamine oxidase inhibitors. Caution should be exercised in patients with severe cardiovascular disease, including hypertension. The possibility of vasovagal episodes exists during laser surgery, particularly in patients with a history of such events. 

Apraclonidine (pora-aminoclonidine) is a relatively nonspecific alphai- and alpha2-adrenoceptor agonist, which is less likely to cross the blood-brain barrier than clonidine. Apraclonidine suppresses aqueous humor flow by 39-44% and lowers intraocular pressure by 20-23% (5). 

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